The present disclosure relates to a seat belt apparatus and a seat belt retractor that retracts and/or withdraws a seat belt by rotating a spool with an electric motor. The disclosure relates more particularly to a seat belt apparatus and a seat belt retractor where the electric motor is controlled by an electronic control unit (ECU).
A conventional seat belt apparatus mounted in a motor vehicle (e.g., an automobile or the like) is configured restrain an occupant to a seat with a seat belt in an event such as a collision of a motor vehicle, rapid braking, etc. The seat belt apparatus includes a seat belt retractor for retracting and/or withdrawing the seat belt. The seat belt is wound on a spool of the retractor when the seat belt is not worn, the seat belt may be withdrawn from the retractor and worn by the occupant. During an event a locking mechanism of the seat belt retractor is activated and the rotation of the spool is prevented in a withdrawing direction so the seat belt cannot be withdrawn. Rotation of the spool may be carried out by an electric motor.